1. Field of the Invention
The present invention relates to the use of base metal catalyst for the decomposition of excess hydrogen peroxide used in chemical processes, disinfecting, or bleaching. The catalyst is copper oxide and manganese dioxide on alumina which is coated onto a substrate. The majority of the peroxide is removed by the catalyst and polishing can be achieved by the addition of small quantities of reagents such as SO.sub.2.
2. Related Art
In some chemical processes, hydrogen peroxide (H.sub.2 O.sub.2) is added to oxidize a chemical intermediate. It is also used as a bleaching agent for products from the textile and paper industries. Hydrogen peroxide is an environmentally friendly chemical for tertiary water treatment since its products of decomposition are water and oxygen. It is expected that hydrogen peroxide will be used more frequently in the future as costs decrease and environmental pressures for clean water increase.
Hydrogen peroxide is sometimes added in excess to a process to accelerate the reaction rate. The excess must be removed before the next stage of processing or before discharging an effluent. In some cases where reverse osmosis is used to recover and/or recycle the waste water, the hydrogen peroxide must be removed in order to protect the osmosis membrane.
Currently, excess hydrogen peroxide is destroyed by adding reducing chemicals such as SO.sub.2 to the stream. While this is an effective method of destruction, the cost can be high, especially if H.sub.2 O.sub.2 concentrations are high.
The present invention is a cost effective method of hydrogen peroxide removal wherein catalyst is placed in the process line. The catalyst can be used in solutions containing from 1 to 500,000 ppm H.sub.2 O.sub.2.